Ex Vivo and In Vivo Analysis of a Novel Porcine Aortic Patch for Vascular Reconstruction

(1) Background: The aim of the present study was the biocompatibility analysis of a novel xenogeneic vascular graft material (PAP) based on native collagen won from porcine aorta using the subcutaneous implantation model up to 120 days post implantationem. As a control, an already commercially available collagen-based vessel graft (XenoSure®) based on bovine pericardium was used. Another focus was to analyze the (ultra-) structure and the purification effort. (2) Methods: Established methodologies such as the histological material analysis and the conduct of the subcutaneous implantation model in Wistar rats were applied. Moreover, established methods combining histological, immunohistochemical, and histomorphometrical procedures were applied to analyze the tissue reactions to the vessel graft materials, including the induction of pro- and anti-inflammatory macrophages to test the immune response. (3) Results: The results showed that the PAP implants induced a special cellular infiltration and host tissue integration based on its three different parts based on the different layers of the donor tissue. Thereby, these material parts induced a vascularization pattern that branches to all parts of the graft and altogether a balanced immune tissue reaction in contrast to the control material. (4) Conclusions: PAP implants seemed to be advantageous in many aspects: (i) cellular infiltration and host tissue integration, (ii) vascularization pattern that branches to all parts of the graft, and (iii) balanced immune tissue reaction that can result in less scar tissue and enhanced integrative healing patterns. Moreover, the unique trans-implant vascularization can provide unprecedented anti-infection properties that can avoid material-related bacterial infections.

Protocols for Paget-Schroetter syndrome and late treatment of chronic subclavian vein obstruction

BACKGROUND

Paget-Schroetter syndrome is a serious condition that if not treated promptly and properly leads to severe sequelae and permanent disability. In its late stage, chronic fibrous obliteration of the vein is rarely amenable to surgical treatment, except in very few select cases.

METHODS

We treated 126 Paget-Schroetter syndrome patients (group I) by implementing an emergency protocol of thrombolysis by catheter-directed infusion, followed by immediate surgery through an anterior subclavian approach entailing (1) decompression of the thoracic inlet and (2) repairing the vein with a vein patch to reestablish its normal caliber. In addition, we treated another selective group of 81 patients (group II) for chronic fibrotic obstruction several months after their original event, but only when the inflow was adequate.

RESULTS

Our acute emergency care resulted in a 100% long-term patency rate in group I, with no sequelae. The patency rate in group II was 100% as well, but in 74% a long vein patch, endovascular stents, or homograft implants were used.

CONCLUSIONS

Implementation of an emergency approach to treat Paget-Schroetter syndrome is highly recommended to prevent the delayed sequelae of permanent subclavian vein obliteration and disability. In chronic obstruction, when feasible, we recommend a long saphenous vein patch, followed by endovascular stent implant.